PROJECT SUMMARY This application is requesting funds to purchase a customized and integrated Multi-Angle Light Scattering (MALS)-based multi-detection system. The seamless integrated instrumentation combines the power of MALS (static light scattering) for accurate molecular mass determination with a) DLS (dynamic light scattering) for a complete picture of molecular sizes and shapes b) SEC (size exclusion chromatography; SEC-MALS) for fractionation capability and characterization of heterogeneous and multivalent complexes, and c) CG (composition gradient; CG-MALS) for stopped flow potential and determination of kinetic and equilibrium dissociation constants (pM to mM) in complex molecular assemblies. The instrumentation is customized to the emergent research needs of the faculty at Baylor College of Medicine, working on complex high molecular weight (MW) assemblies (e.g. multi-protein, multi- protein:DNA/RNA, membrane proteins and transporters, viral-like particles and viral proteins, therapeutic antibodies, and amyloid aggregates) and challenging systems (e.g. intrinsically disordered proteins, PTM- conjugated proteins and drug-bound or conjugated protein targets). There are representative 13 Major Users and 3 Minor Users. Macromolecular characterization of the various protein targets is essential in understanding the protein's cellular function and dysfunction leading to many life-threatening (e.g. infectious, cancer and neurodegenerative) diseases. There are three known private SEC-MALS instruments and no shared equipment in the region. There is also no known CG-MALS available, which is a critical technique for users to characterize molecular interactions of complex molecular species. Furthermore, the high volume of anticipated usage (including high throughput routine screening), and the sensitivity of most samples compel the users to request this shared instrumentation. The equipment will be part of a biomolecular characterization core that will serve BCM investigators, as well as researchers in the (TMC) Texas Medical Center (e.g. Rice University, MD Anderson Cancer Center), Texas and beyond. In addition, the MALS instrumentation will be an essential technical resource in the global strategic plans of BCM and TMC institutions for precision medicine and translational research.